During the 1960s, the Jean Lesage Quebec government mandated Castonguay to chair a Commission (with Gerard Nepveu)- The Commission on health care and social services (Commission d’enquête sur les services de santé et les services sociaux)- on the state of health care in Quebec much of which, before the Quiet Revolution, was still largely under the jurisdiction of the Clergy. The result was the Castonguay-Nepveu Report published in 1967. This report recommended a new state-run health insurance policy, a new health care network, as well as a new network of social service clinics now known as the CLSC. The plan was to give a broader access to health and psychiatric care for the Quebec population. Major changes were made following the recommendation, most notably the introduction of hospitalisation and medicationinsurance. Castonguay is so closely identified with health care in Quebec that many people refer to the Quebec health card (Carte d’assurance-maladie au Québec) as a Castonguette.[1]

In 2007, the minority Liberal government of Quebec appointed Castonguay to a closed-door committee examining the health-care system's finances. Castonguay is a long-serving advocate of greater privatization, user fees and private insurance.[2]

The Castonguay task force released in February 2008 said Quebec residents should pay $25 for every visit to a doctor. The report also called for an increase of up to one percentage point in the Quebec sales tax to help pay for medicare. Castonguay said health care is growing 5.8 per cent a year as a share of the provincial budget, while total government spending increases 3.9 per cent annually.[3]

Most of the report was publicly dismissed by the government of the day.

Forty years after being one of the pioneers of socialized medicine, Castonguay's commission advocates both an increased role for private enterprise in medicine and increased public investment in the socialized system both through taxes and through user fees. Castonguay was quoted as saying "We are proposing to give a greater role to the private sector so that people can exercise freedom of choice."[4] While concerned about the financial stresses the system places on the government, Castonguay does not advocate dismantling publicly financed health insurance altogether.[5][6]